A post on the Diablo III Forums from community manager Lylirra confirms that Blizzard is looking to follow player feedback and address some of the simple database oversights that impede the functionality of the game's auction house (thanks VG247 via Diablo N). Here's word:

Thanks for the feedback! We're looking to bump the number of Preferred Stats slots from 3 up to 6. We're also looking to bump the number of digits in the "Min Value" window from 3 to 5 (so you can search for Preferred Stat values higher than "999").